Assessment of the number of mast cells in the soft palate of dogs affected by brachycephalic obstructive airway syndrome.

BACKGROUND: Oedema is described in the soft palate of dogs affected by brachycephalic obstructive airway syndrome (BOAS). Activated mast cells (MCs) release vasoactive mediators that temporarily increase vascular permeability.

METHODS: Data and caudal soft palate tissue were prospectively collected from a population of dogs undergoing surgical management of BOAS and a control group of greyhound cadavers with no previous history of respiratory signs. Histological assessment was performed to quantify the number of MCs within the lamina propria of each group.

RESULTS: The mean number of MCs in the BOAS group (53 MCs/10 400× high-power fields [HPF]; standard deviation [SD] = 23) was significantly greater than that in the greyhound group (24 MCs/10 400×HPF; SD = 10).

LIMITATIONS: The small size of the control group and the heterogeneous nature of the dogs in the BOAS group limit the generalisability of the findings. The use of different surgical techniques in the BOAS group may have also affected the degree of inflammation present within the samples. The cohort was not screened for concurrent disease processes that could potentially increase the number of circulating MCs.

CONCLUSION: This study demonstrated a statistically significant difference between the numbers of MCs in the soft palate of brachycephalic dogs with clinically significant BOAS and the greyhound control group.